In what South Korean prosecutors are calling the most significant industrial espionage case in national history, a group of former Samsung Electronics employees has been indicted for leaking cutting-edge 10-nanometer-class DRAM technology to China’s ChangXin Memory Technologies (CXMT). The breach, which utilized low-tech methods like hand-copying secrets to bypass digital security, has caused an estimated VND 95 trillion ($3.7 billion) in lost sales for Samsung in 2025 alone, effectively accelerating China’s semiconductor independence by years.
Low-Tech Methods for High-Tech Secrets
Despite Samsung’s state-of-the-art cybersecurity and "clean room" protocols, the primary suspect, a former researcher identified as Mr. B who successfully bypassed security through a surprisingly primitive method.
- Hand-Written Blueprints: Aware that USB drives and cloud uploads would trigger immediate digital alarms, Mr. B spent his final weeks at Samsung manually transcribing over 600 steps of the 10nm DRAM manufacturing process onto 12 pages of paper.
- Invisible Tracks: By hand-drawing technical diagrams and equipment specifications, the suspects left no digital footprint. These notes were then smuggled out of the facility and used as a "recipe book" to reconstruct Samsung’s proprietary manufacturing flow at CXMT in China.
- The $1.2 Billion "Gift": The leaked data concerned technology that Samsung had spent VND 30 trillion ($1.2 billion) and five years to develop. This allowed CXMT to become the first Chinese firm to mass-produce 18nm DRAM in 2023, skipping years of costly R&D.
A Systematic Recruitment Campaign
The leak was not a lone-wolf operation, but a coordinated effort led by "Mr. A," a former Samsung executive who moved to CXMT to lead its second-generation development team.
- Poaching the Experts: Mr. A systematically targeted his former colleagues, luring at least 20 high-level Samsung engineers to China with "golden hellos."
- The Price of Betrayal: Recruits were reportedly offered annual salaries three to five times higher than their Samsung compensation, with some top engineers receiving post-tax packages exceeding VND 9.5 billion ($370,000) per year.
- Shell Companies and Codes: To avoid detection by the South Korean National Intelligence Service (NIS), the group operated through shell companies and frequently changed office locations. They communicated using encrypted devices and pre-arranged "emergency codes" to alert each other if they were being followed or if travel bans were imminent.
Trillions in Damage
The impact of this technology transfer has sent shockwaves through the global semiconductor market, threatening the dominance of the "Big Three" (Samsung, SK Hynix, and Micron).
- Market Erosion: Prosecutors estimate that Samsung’s sales decline due to this specific leak reached VND 95 trillion ($3.7 billion) in 2024–2025.
- China's Leapfrog: With the stolen IP, CXMT’s global market share surged to 7% in 2024, positioning it as the world's fourth-largest DRAM maker. This stolen foundation is now being used by China to accelerate the production of High-Bandwidth Memory (HBM), a critical component for AI chips.
- National Security Threat: The South Korean government has reclassified 10nm DRAM as a "National Core Technology," meaning any future leaks could carry even harsher penalties, including life imprisonment.
Legal Consequences and Prosecution
On December 23, 2025, the Seoul Central District Prosecutors' Office officially indicted 10 individuals involved in the scheme.
- Sentencing: While the lead suspect in the first-generation leak was sentenced to seven years in prison, prosecutors are pushing for much steeper terms of up to 20 years for the recent group of executives, citing the "irreversible damage" to the national economy.
- Closing the Gaps: In response, Samsung has further tightened its security, implementing AI-driven behavioral monitoring and stricter non-compete clauses for employees in core R&D divisions.
The case serves as a stark reminder that in the high-stakes global "chip war," the most dangerous threat often comes from within, armed with nothing more than a pen and a notepad.